Can We Access Private Data Members of a Class without using a Member or a Friend Function in C++?
The idea of Encapsulation is to bundle data and methods (that work on the data) together and restrict access of private data members outside the class. In C++, a friend function or friend class can also access private data members.
So, is it possible to access private members outside a class without friend? Yes, it is possible using pointers. Although it’s a loophole in C++, yes it’s possible through pointers.
x = 3 y = 9
Explanation: In the above program, a is an object of class A. The address of the object is assigned to integer pointer p by applying typecasting. The pointer p points to private member x. The integer value is assigned to *p, that is, x. Address of object a is increased and by accessing the memory location value 9 is assigned to y. The p– statement sets the memory location of x. Using the cout statement contains of x is displayed.
x = 5 y = 4 z = 3
Note: In the above way of accessing private data members is not at all a recommended way of accessing members and should never be used. Also, it doesn’t mean that the encapsulation doesn’t work in C++. The idea of making private members is to avoid accidental changes. The above change to data is not accidental. It’s an intentionally written code to fool the compiler.
This article is contributed by Ashish Kumar. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.